RedisLabs at AWS re:Invent 2014

Redis is an open source advanced key-cache and store, generally used as a very fast in memory database. However, with the enhancements pioneered by RedisLabs over the past two years, you can move multiple database installations from datacenters to a cloud environment and treat it as a real database with zero touch , all the while preserving a high level of performance. With over 67,000 databases under management today, RedisLabs claims the fastest database performance in the world and exceptional reliability.

There is a free tier of service available online.There is also a RedisLabs on premise cluster that can be evaluated for datacenter use.